1. Field of the Invention
The present invention relates to the field of printing presses. More particularly, the invention relates to a convenient method for quickly loading printing cylinders into a printing press.
2. Description of the Related Art
Previously, to install a printing press cylinder (xe2x80x9cplate rollxe2x80x9d) in a printing press, an operator would align the cylinder bearings with holes in press adjusting arms and simultaneously skewer a shaft through the holes and the cylinder therebetween. After skewering the cylinder, the operator had to adjust the press adjusting arms to achieve desired ink and impression settings. Adjusting the arms was dependent on the size of the cylinder which, in turn, was reflective of the image repeat length.
While close-fit tolerances of the adjusting arms, shaft, and cylinder facilitate stable and quality printing, a first problem arises in that the tolerances also impede loading of the printing plate cylinder. A second problem arises in that although the cylinder may be properly loaded, the conventional method still requires additional user intervention by requiring that the coarse ink and impression settings be adjusted to coordinate with the size and location of the cylinder.
An alternative method for loading and registering the cylinder involves clamping the two ends of the cylinder in cam followers; the actual contact of the cam followers occurring against wheels on the printing press assembly. However, although the cam followers help minimize the first of the two problems, the second problem still remains, i.e., user intervention is still required to register the ink and impression settings.
Thus, although a number of methods exist for positioning printing press cylinder rolls in the printing nip of a printing press, these approaches have proven to be imperfect for the previously detailed reasons. Accordingly, a new apparatus and method are needed which can quickly and effectively lower a printing press cylinder roll into the printing nip.
The invention herein contains multiple embodiments including an adjustable arm adapted for use in a printing press, a printing press, and a method for loading a printing press roll in a printing press. A first embodiment of the adjustable arm assembly includes a first stationary plate, a first movable plate movably connected to the first stationary plate, and a speed control mechanism. The first movable plate includes one of a catch or a capture knob assembly adapted to engage a first end of a printing press roll. The speed control mechanism is adapted to control the speed by which a printing press cylinder roll is lowered, is connected to the first movable plate, and is adapted to be connected to an inner surface of a printing press.
In a second embodiment of the adjustable arm assembly, the speed control mechanism may be at least one of an air cylinder and a hydraulic cylinder. In addition, the catch may comprises a semicircular rib which, in turn, may be adapted to support a boss projecting from a cylindrical printing press roll. Further, the rib may be connected to a plate. In addition, the catch may also include a bore block adapted to engage an end of a shaft of a printing press roll. In another embodiment, the first movable plate may be connected to the first stationary plate by a plurality of wheels.
Another embodiment of the adjustable arm assembly may include a second stationary plate and a second movable plate movably connected to the second stationary plate by a plurality of wheels. In this embodiment, the second movable plate may include the other of the catch or capture knob assembly, wherein the other of the catch or capture knob assembly is adapted to engage a second end of a printing press roll.
Another adjustable arm assembly embodiment may include a disengagement mechanism connected to the first stationary plate. Further, the disengagement mechanism may include a rotatable block, a wheel mechanism adapted to rotate the rotatable block, and/or a drive mechanism adapted to push the wheel mechanism so as to cause a rotation of the rotatable block. In addition, the drive mechanism may be at least one of an air cylinder and a hydraulic cylinder. Similarly, in this embodiment, the speed control mechanism may be at least one of a second air and a second hydraulic cylinder.
In an embodiment of the adjustable arm assembly having a disengagement mechanism therein, the assembly may additionally include a rod engaged with a first movable plate and adapted to be releasably engaged with a bore in a rotatable block of the disengagement mechanism.
Another embodiment of the adjustable arm assembly may include a disengagement mechanism which is connected to the first stationary plate and which is adapted to inhibit movement of the first movable plate with respect to the first stationary plate.
As previously mentioned, the invention also pertains to a printing press. A first embodiment of the printing press according to the present invention includes a housing having an inner surface, an adjustable arm assembly connected to the inner surface, and at least one roll adapted to be contacted by a printing press roll when the printing press roll is lowered by the adjustable arm assembly into the press. In this embodiment, the adjustable arm assembly includes a first stationary plate, a first movable plate movably connected to the first stationary plate, and a speed control mechanism. Further, the first movable plate includes a catch adapted to engage a first end of the printing press roll. In addition, the speed control mechanism is adapted to control the speed by which the printing press cylinder roll is lowered, is connected to the first movable plate, and is adapted to be connected to an inner surface of a printing press.
In a second another embodiment of the printing press, the first movable plate may be connected to the first stationary plate by a plurality of wheels. In another embodiment of the printing press, the at least one roll may be an anilox roll and/or an impression roll. In another embodiment, the speed control mechanism may be at least one of an air cylinder and a hydraulic cylinder. In yet another embodiment, the catch may include a semicircular rib. Further, the semicircular rib may be adapted to support a boss projecting from a cylindrical printing press roll. In addition, the rib may be connected to a plate and the catch may also include a bore block adapted to engage an end of a shaft of a printing press roll.
Another embodiment of the printing press may include a second stationary plate and a second movable plate movably connected to the second stationary plate by a plurality of wheels. Further, the second movable plate may include a capture knob assembly adapted to engage a second end of a printing press roll. In yet another embodiment of the printing press, a disengagement mechanism may be provided which is connected to the first stationary plate. Further, the disengagement mechanism may include a rotatable block, a wheel mechanism which is adapted to rotate the rotatable block, and a drive mechanism adapted to push the wheel mechanism so as to cause a rotation of the rotatable block. In addition, the drive mechanism may be at least one of an air cylinder and a hydraulic cylinder. Similarly, the speed control mechanism may be at least one of a second air and a second hydraulic cylinder.
Another embodiment of the printing press may include a rod which is engaged with the first movable plate and which is adapted to be releasably engaged with a bore in a rotatable block. In addition, another embodiment of the adjustable arm assembly may include a disengagement mechanism which is connected to the first stationary plate and which is adapted to inhibit movement of the first movable plate with respect to the first stationary plate.
A method for loading a printing press cylinder roll in a printing press is also contemplated by the current invention. This method includes: (a) positioning a right end of a printing press cylinder roll in a right adjustment arm assembly; (b) positioning a left end of the printing press cylinder roll in a left adjustment arm assembly; (c) actuating a plate roll capturing knob assembly to lock the printing press cylinder roll with respect to the adjustment arm assemblies; and (d) lowering the printing press cylinder roll and the left and right adjustment arm assemblies from an insertion position to a loaded position in which the printing press cylinder roll contacts at least one roll in the printing press.
The aforementioned method may additionally include (e) limiting the speed by which the printing press cylinder roll is lowered. Further, the step of limiting the speed by which the printing press cylinder roll is lowered may be performed by an air or hydraulic cylinder.
Additionally or alternatively, the method may include (e) (or (f)) fine-tuning the orientation of the printing press cylinder roll with respect to the at least one roll in the printing press. Further, the step of fine-tuning the orientation of the printing press cylinder roll with respect to the at least one roll in the printing press may include turning a rod engaged with a disengagement mechanism and a movable plate of one of the adjustable arm assemblies.
The method may also include: (e) engaging a disengagement mechanism when the printing press cylinder roll contacts the at least one roll in the printing press; and (f) fine-tuning the orientation of the printing press cylinder roll with respect to the at least one roll in the printing press. In addition, the disengagement mechanism may include a threaded rod. Further, the disengagement mechanism may also include a rotatable block, a wheel mechanism which is adapted to rotate the rotatable block adapted to engage the threaded rod, and a drive mechanism adapted to push the wheel mechanism so as to cause a rotation of the rotatable block.
Another embodiment of the method, the step of actuating a plate roll capturing knob assembly to lock the printing press cylinder roll with respect to the adjustment arm assemblies comprises: (i) turning a capture knob on the right adjustable arm assembly to force a plunger into the right end of the printing press cylinder roll; and (ii) forcing a left end of the printing press cylinder roll to engage a catch formed in the left adjustable arm assembly.
Another embodiment of the method may include, before the steps of positioning the right end of a printing press cylinder roll in the right adjustment arm assembly and positioning the left end of the printing press cylinder roll in the left adjustment arm assembly, the step of: raising automatically the right and left adjustment arm assemblies to a cylinder roll loading position. Further, the step of automatically raising the right and left adjustment arm assemblies may involve actuating the left and right adjustable arm assemblies simultaneously.
The method may also include: (e) replacing the printing press cylinder roll with a second printing press cylinder roll. Further, the step of replacing the printing press cylinder roll may be automated. In addition, the method could also additionally include: (f) adjusting the second printing press cylinder roll with respect to the at least one roll in the printing press.
An embodiment of the method may also include: (e) establishing automatically a predetermined clearance between the printing press cylinder roll and the at least one roll of the printing press. Further, the step of establishing automatically a predetermined clearance between the printing press cylinder roll and the at least one roll of the printing press may include: (i) engaging a disengagement mechanism to lock the right and left adjustment arm assemblies in the loaded position; and (ii) activating an adjustment arm raising mechanism to push the right and left adjustment arms assemblies towards the insertion position to attain the predetermined clearance. In addition, the predetermined clearance is between about 0.00001xe2x80x3 and about 0.01xe2x80x3.
Another embodiment of the method may include: (e) establishing automatically a predetermined clearance between the printing press cylinder roll and the at least one roll of the printing press; and (f) fine-tuning the orientation of the printing press cylinder roll with respect to the at least one roll in the printing press. Further, the step of fine-tuning the orientation of the printing press cylinder roll with respect to the at least one roll in the printing press may include: turning a rod engaged with a disengagement mechanism and a movable plate of one of the adjustable arm assemblies.
Finally, in any of the previous method embodiments, the at least one roll in the printing press may be an anilox roll and/or an impression roll.
These and other features, aspects, and advantages of the present invention will become more apparent from the following description, appended claims, and accompanying exemplary embodiments shown in the drawings.